/Engine/Source/Runtime/Engine/Classes/Components/InputComponent.h
Indicates that the InputComponent is interested in knowing the Axis value (via GetAxisValue) but does not want a delegate function called each frame. Returned reference is only guaranteed to be valid until another axis is bound.
[FInputAxisBinding](API\Runtime\Engine\Components\FInputAxisBinding) & BindAxis ( const [FName](API\Runtime\Core\UObject\FName) AxisName )